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Autonomic control of heart rate is well known in adult subjects, but limited data are available on the development of the heart rate control during childhood and adolescence. Continuous 12-lead electrocardiograms were recorded in 1045 healthy children and adolescents (550 females) aged 4 to 19 years during postural manoeuvres involving repeated 10-min supine, unsupported sitting, and unsupported standing positions. In each position, heart rate was measured, and heart rate variability indices were evaluated (SDNN, RMSSD, and high (HF) and low (LF) frequency components were obtained). Quasi-normalized HF frequency components were defined as qnHF = HF/(HF + LF). These measurements were, among others, related to age using linear regressions. In supine position, heart rate decreases per year of age were significant in both sexes but lower in females than in males. In standing position, these decreases per year of age were substantially lowered. RMSSD and qnHF indices were independent of age in supine position but significantly decreased with age in sitting and standing positions. Correspondingly, LF/HF proportions showed steep increases with age in sitting and standing positions but not in the supine position. The study suggests that baseline supine parasympathetic influence shows little developmental changes during childhood and adolescence but that in young children, sympathetic branch is less responsive to vagal influence. While vagal influences modulate cardiac periods in young and older children equally, they are less able to suppress the sympathetic influence in younger children.
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Sistema Nervoso Autônomo , Frequência Cardíaca , Humanos , Frequência Cardíaca/fisiologia , Adolescente , Feminino , Masculino , Criança , Pré-Escolar , Sistema Nervoso Autônomo/fisiologia , Adulto Jovem , Decúbito Dorsal , Eletrocardiografia/métodos , Postura/fisiologia , AdultoRESUMO
BACKGROUND: Bazett formula is frequently used in paediatric screening for the long QT syndrome (LQTS) and proposals exist that using standing rather than supine electrocardiograms (ECG) improves the sensitivity of LQTS diagnosis. Nevertheless, compared to adults, children have higher heart rates (especially during postural provocations) and Bazett correction is also known to lead to artificially prolonged QTc values at increased heart rates. This study assessed the incidence of erroneously increased QTc values in normal children without QT abnormalities. METHODS: Continuous 12-lead ECGs were recorded in 332 healthy children (166 girls) aged 10.7 ± 2.6 years while they performed postural manoeuvring consisting of episodes (in the following order) of supine, sitting, standing, supine, standing, sitting, and supine positions, each lasting 10 min. Detailed analyses of QT/RR profiles confirmed the absence of prolonged individually corrected QTc interval in each child. Heart rate and QT intervals were measured in 10-s ECG segments and in each segment, QTc intervals were obtained using Bazett, Fridericia, and Framingham formulas. In each child, the heart rates and QTc values obtained during supine, sitting and standing positions were averaged. QTc durations by the three formulas were classified to < 440 ms, 440-460 ms, 460-480 ms, and > 480 ms. RESULTS: At supine position, averaged heart rate was 77.5 ± 10.5 beat per minute (bpm) and Bazett, Fridericia and Framingham QTc intervals were 425.3 ± 15.8, 407.8 ± 13.9, and 408.2 ± 13.1 ms, respectively. At sitting and standing, averaged heart rate increased to 90.9 ± 10.1 and 100.9 ± 10.5 bpm, respectively. While Fridericia and Framingham formulas showed only minimal QTc changes, Bazett correction led to QTc increases to 435 ± 15.1 and 444.9 ± 15.9 ms at sitting and standing, respectively. At sitting, Bazett correction identified 51, 4, and 0 children as having the QTc intervals 440-460, 460-480, and > 480 ms, respectively. At sitting, these numbers increased to 118, 11, and 1, while on standing these numbers were 151, 45, and 5, respectively. Irrespective of the postural position, Fridericia and Framingham formulas identified only a small number (< 7) of children with QT interval between 440 and 460 ms and no children with longer QTc. CONCLUSION: During screening for LQTS in children, the use of Bazett formula leads to a high number of false positive cases especially if the heart rates are increased (e.g. by postural manoeuvring). The use of Fridericia formula can be recommended to replace the Bazett correction not only for adult but also for paediatric ECGs.
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Síndrome do QT Longo , Adolescente , Adulto , Criança , Eletrocardiografia , Família , Feminino , Frequência Cardíaca , Humanos , Síndrome do QT Longo/diagnósticoRESUMO
NGAL (neutrophil gelatinase-associated lipocalin) is an acute phase protein, participating in antibacterial immunity. NGAL forms a complex with metalloproteinase 9 (MMP-9), thereby increasing its activity and preventing its degradation. NGAL is freely filtered through the glomerular membrane and reabsorbed by endocytosis in the proximal tubule. NGAL detected in urine is produced mainly in the distal nephron. Elevated serum and urine NGAL allows diagnosis of acute kidney injury approximately 24 hours earlier than plasma creatinine concentration. Increased levels of NGAL were detected in patients with acute myocardial infarction, heart failure or stroke and were demonstrated to be strong predictors of adverse prognosis.
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Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Lipocalinas/sangue , Proteínas Proto-Oncogênicas/sangue , Proteínas de Fase Aguda/fisiologia , Biomarcadores/sangue , Humanos , Lipocalina-2 , Lipocalinas/fisiologia , Prognóstico , Proteínas Proto-Oncogênicas/fisiologiaRESUMO
INTRODUCTION: Cardiogenic shock (CS) is the leading cause of mortality in patients with acute myocardial infarction (AMI). Inflammatory response seems to be common response in patients with AMI, especially those with CS. We have therefore conducted a study to determine diagnostic and prognostic utility of interleukin 6 (IL6) levels in the cohort of patients with cardiogenic and septic shock (SS) and in a control group of patients with uncomplicated AMI. METHODS: In this prospective study 71 patients fulfilled the inclusion criteria: 30 patients with cardiogenic shock, 21 patients with septic shock and 20 patients with ST elevation myocardial infarction (STEMI). Plasma levels of IL6 were measured at 8 time points. The main endpoint was 3 month mortality. RESULTS: We have shown that the highest IL6 levels during the first week were recorded in patients with septic shock with peak value at admission. The maximum level of IL6 was detected between 12 to 24 hours after the onset of MI among patients with cardiogenic shock. According to Receiver operating characteristic (ROC) statistics levels of IL6 > 357 pg/ml at admission (AUC 0.730, p = 0.031) were typical for patients with CS in comparison with control group of STEMI patients. Values of IL6 > 1 237 pg/ml at admission and > 1 071 pg/ml at 24 hours (after admission?) were typical for thouse in septic shock in comparison with CS patients. We found only a non-significant trend of IL6 for the prediction of mortality in the cohort of CS patients for levels 1 854 pg/ml (AUC 0.769, p = 0.066) sampled 12 hours after admission. There was no association of plasma levels of IL6 with mortality in septic shock patients. CONCLUSIONS: Patients with cardiogenic shock demonstrated more pronounced cytokine response as evidenced by increased levels of IL6 compared to patients with uncomplicated STEMI. Levels of IL6 peaked in SS patients at admission, in CS patients 12-24 hours after admission. In daily clinical practice routine measurement of IL6 levels for prediction of prognosis both in cardiogenic and septic shock are of little value mainly due to significant interindividual variability of IL6 values.
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Interleucina-6/sangue , Infarto do Miocárdio/sangue , Choque Cardiogênico/sangue , Choque Séptico/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de TempoRESUMO
Background/Objective: The relationship between heart rate and heart rate variability (HRV) indices has been repeatedly studied in adults but limited data are available on the relationship in paediatric populations. Methods: Continuous 12-lead electrocardiograms were recorded in 1016 healthy children and adolescents (534 females) aged 4 to 19 years during postural manoeuvres with rapid changes between 10-min positions of supine â sitting â standing â supine â standing â sitting â supine. In each position, the averaged RR interval was measured together with four HRV indices, namely the SDNN, RMSSD, quasi-normalised high-frequency components (qnHF), and the proportions of low- and high-frequency components (LF/HF). In each subject, the slope of the linear regression between the repeated HRV measurements and the corresponding RR interval averages was calculated. Results: The intra-subject regression slopes, including their confidence intervals, were related to the age and sex of the subjects. The SDNN/RR, RMSSD/RR, and qnHF/RR slopes were significantly steeper (p < 0.001) and the (LF/HF)/RR slopes were significantly shallower (p < 0.001) in younger children compared to older children and adolescents. Conclusions: The study suggests that sympathetic and vagal influences on heart rate are present in both younger and older children. With advancing age, the sympatho-vagal balance gradually develops and allows the vagal control to suppress the sympathetic drive towards higher heart rates seen in younger age children.
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Heart rate is under constant autonomic influence but the development of the influence in children is not fully understood. Continuous electrocardiograms were obtained in 1045 healthy school-age children (550 females) during postural provocations with body position changes between supine, sitting, standing, supine, standing, sitting and supine (in this order), 10 min in each position with position changes within 20 s. Heart rate was measured in each position and speed of heart rate changes between positions were assessed by regressions of rates versus timing of individual cardiac cycles. Supine heart rate was gradually decreasing with age: 82.32 ± 9.92, 74.33 ± 9.79, 67.43 ± 9.45 beats per minute (bpm) in tertile age groups < 11, 11-15, > 15 years, respectively (p < 0.0001), with no significant sex difference. Averaged speed of heart rate changes differed little between sexes and age groups but was significantly faster during rate deceleration than acceleration (e.g., supine â standing: 2.99 ± 1.02 vs. 2.57 ± 0.68 bpm/s, p < 0.0001). The study suggests that in children, vagal heart rate control does not noticeably change between ages of approximately 6-19 years. The gradual resting heart rate decrease during childhood and adolescence is likely caused by lowering of cardiac sympathetic influence from sympathetic overdrive in small children to adult-like sympatho-vagal balance in older adolescents.
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Eletrocardiografia , Frequência Cardíaca , Postura , Humanos , Frequência Cardíaca/fisiologia , Feminino , Criança , Masculino , Adolescente , Postura/fisiologia , Sistema Nervoso Autônomo/fisiologia , Decúbito Dorsal/fisiologia , Nervo Vago/fisiologiaRESUMO
BACKGROUND: Soluble ST2 (sST2) is an interleukin-33 receptor. sST2 was found to be an independent prognostic factor in patients with myocardial infarction, sepsis and heart failure. OBJECTIVES: To assess sST2 levels in patients with cardiogenic shock (CS) and septic shock (SS), and to evaluate the prognostic value of sST2 for short-term mortality. METHODS: The present prospective observational study evaluated 32 patients with CS, 17 patients with SS and 61 patients with ST segment elevation myocardial infarction (STEMI )(control group). Samples of serum were collected eight times and the follow-up time was three months. RESULTS: sST2 levels were elevated from admission in SS patients relative to patients with CS and STEMI, who exhibited peak sST2 levels 24 h after admission. On admission, CS patients had a median (5th percentile; 95th percentile) sST2 level of 62.5 pg/mL (8.3 pg/mL; 315.8 pg/mL) and SS patients had a median sST2 level of 216.4 pg/mL (46.8 pg/mL; 364.4 pg/mL). ROC analysis found sST2 to be a biomarker that could distinguish between CS and SS at admission (area under the curve [AUC] 0.813; P<0.01) with a cut-off value of 210.4 pg/mL. Patients with STEMI had significantly lower sST2 levels at admission (20.3 pg/mL (4.2 pg/mL; 339.8 pg/mL) compared with CS patients. The AUC of the ROC analysis was 0.671 (P=0.007) for the detection of CS in patients with STEMI. Only a weak correlation was observed between sST2 and B-type natriuretic peptide (r=0.376, P=0.05) and sST2 and N-terminal pro-B-type natriuretic peptide (r=0.496, P=0.019). No statistically significant differences were observed in sST2 levels in patients with CS and SS relative to three-month mortality. CONCLUSION: Levels of sST2 at admission are significantly higher in patients with SS compared with CS. sST2 could be a diagnostic marker to distinguish SS and CS as well as CS and STEMI at the time of admission. Levels of sST2 are related to levels of natriuretic peptides in CS but not in SS. sST2 levels are not a suitable prognostic marker for patients with CS and SS.
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Sepsis is a clinical syndrome characterized by a dysregulated response to infection. It represents a leading cause of mortality in ICU patients worldwide. Although sepsis is in the point of interest of research for several decades, its clinical management and patient survival are improving slowly. Monitoring of the biomarkers and their combinations could help in early diagnosis, estimation of prognosis and patient's stratification and response to the treatment. Circulating soluble endoglin (sEng) is the cleaved extracellular part of transmembrane glycoprotein endoglin. As a biomarker, sEng has been tested in several pathologic conditions where its elevation was associated with endothelial dysfunction. In this study we have tested the ability of sEng to predict mortality and its correlation with other clinical characteristics in the cohort of septic shock patients (n = 37) and patients with severe COVID-19 (n = 40). In patients with COVID-19 sEng did not predict mortality or correlate with markers of organ dysfunction. In contrast, in septic shock the level of sEng was significantly higher in patients with early mortality (p = 0.019; AUC = 0.801). Moreover, sEng levels correlated with signs of circulatory failure (required dose of noradrenalin and lactate levels; p = 0.002 and 0.016, respectively). The predominant clinical problem in patients with COVID-19 was ARDS, and although they often showed signs of other organ dysfunction, circulatory failure was exceptional. This potentially explains the difference between sEng levels in COVID-19 and septic shock. In conclusion, we have confirmed that sEng may reflect the extent of the circulatory failure in septic shock patients and thus could be potentially used for the early identification of patients with the highest degree of endothelial dysfunction who would benefit from endothelium-targeted individualized therapy.
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Background: Heart failure (HF) patients are at higher risk of severe coronavirus disease 2019 (COVID-19). The Omicron variant has many novel mutations including those in the spike protein, leading to questions about vaccine effectiveness. The aim of this analysis was to evaluate the effectiveness of the COVID-19 vaccine with or without a booster (i.e., after the third dose) during the Omicron variant wave. Methods: Chronic heart failure patients in the Czech Republic were included in the analysis. COVID-19 infection was monitored from January 1st 2022 to March 31st 2022. The analysis was conducted on data collected in the National Health Information System. Vaccine effectiveness of vaccinated (with or without booster) vs. unvaccinated patients was analyzed for incidence of COVID-19, COVID-19-related hospitalizations, COVID-19 related intensive care unit admissions, and COVID-19 related mechanical ventilation/extracorporeal membrane oxygenation treatment. Findings: From a total 165,453 HF patients in the Czech Republic, 9,728 contracted COVID-19 (22.9% of them not vaccinated, 23.2% vaccinated and 53.8% vaccinated and boosted). Risk of intensive care unit (ICU) hospitalization was 7.6% in the unvaccinated group, 4.8% in the vaccinated group and 2.9% in the boosted group. The calculated effectiveness of the COVID-19 vaccine in prevention of ICU hospitalization in the vaccinated group was 41.9 and 76.6% in the boosted group. Interpretation: The results demonstrated moderate vaccine effectiveness in the prevention of severe COVID-19 in vaccinated but not boosted HF patients. Much stronger effectiveness was found in those who were vaccinated and boosted.
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Septic shock is a major cause of mortality in ICU patients, its pathophysiology is complex and not properly understood. Oxidative stress seems to be one of the most important mechanisms of shock progression to multiple organ failure. In the present pilot study, we have analysed eight oxidative-stress-related biomarkers in seven consecutive time points (i.e., the first seven days) in 21 septic shock patients admitted to the ICU. Our objective was to describe the kinetics of four biomarkers related to pro-oxidative processes (nitrite/nitrate, malondialdehyde, 8-oxo-2'-deoxyguanosine, soluble endoglin) compared to four biomarkers of antioxidant processes (the ferric reducing ability of plasma, superoxide dismutase, asymmetric dimethylarginine, mid-regional pro-adrenomedullin) and four inflammatory biomarkers (CRP, IL-6, IL-10 and neopterin). Furthermore, we analysed each biomarker's ability to predict mortality at the time of admission and 12 h after admission. Although a small number of study subjects were recruited, we have identified four promising molecules for further investigation: soluble endoglin, superoxide dismutase, asymmetric dimethylarginine and neopterin.
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Indirect evidences in reviews and case reports on Takotsubo syndrome (TTS) support the fact that the existence of oxidative stress (OS) might be its common feature in the pre-acute stage. The sources of OS are exogenous (environmental factors including pharmacological and toxic influences) and endogenous, the combination of both may be present, and they are being discussed in detail. OS is associated with several pathological conditions representing TTS comorbidities and triggers. The dominant source of OS electrones are mitochondria. Our analysis of drug therapy related to acute TTS shows many interactions, e.g., cytostatics and glucocorticoids with mitochondrial cytochrome P450 and other enzymes important for OS. One of the most frequently discussed mechanisms in TTS is the effect of catecholamines on myocardium. Yet, their metabolic influence is neglected. OS is associated with the oxidation of catecholamines leading to the synthesis of their oxidized forms - aminochromes. Under pathological conditions, this pathway may dominate. There are evidences of interference between OS, catecholamine/aminochrome effects, their metabolism and antioxidant protection. The OS offensive may cause fast depletion of antioxidant protection including the homocystein-methionine system, whose activity decreases with age. The alteration of effector subcellular structures (mitochondria, sarco/endoplasmic reticulum) and subsequent changes in cellular energetics and calcium turnover may also occur and lead to the disruption of cellular function, including neurons and cardiomyocytes. On the organ level (nervous system and heart), neurocardiogenic stunning may occur. The effects of OS correspond to the effect of high doses of catecholamines in the experiment. Intensive OS might represent "conditio sine qua non" for this acute clinical condition. TTS might be significantly more complex pathology than currently perceived so far.
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INTRODUCTION: Cardiogenic shock is a frequent complication of acute myocardial infarction. Similar to ischemia/reperfusion injury, excessive production of reactive oxygen species can be expected in those who experience cardiogenic shock. The aims of this study were to describe the extent and time course of oxidative stress and evaluate the prognostic value of oxidative stress markers in patients who experienced ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock. METHODS: Plasma/serum levels of selected biomarkers of oxidative stress (oxidised guanine species (OGS), malondialdehyde, and glutathione peroxidase 3) and markers, which simultaneously reflect severe cellular damage (ferric ion reducing antioxidant power (FRAP), Cu/Zn-superoxide dismutase (SOD), and glutathione) were measured seven times per week in a prospective cohort of 82 patients with STEMI complicated by cardiogenic shock. RESULTS: We found elevated OGS levels in patients who died during three months, which persisted significantly increased the next 12 h compared to surviving patients. A similar time course pattern also exhibited concentrations of FRAP and SOD. The other markers did not change significantly and did not show differences between surviving and non-surviving patients during the monitored period. In addition, a strong relationship between OGS, FRAP, and SOD levels (on admission and 12 h after admission) and 3-month mortality was found. CONCLUSION: Levels of OGS, FRAP, and SOD within 12 h after hospital admission were revealed as early predictors of the adverse development of STEMI complicated by cardiogenic shock.
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Infarto do Miocárdio , Choque Cardiogênico , Estudos de Coortes , Humanos , Infarto do Miocárdio/complicações , Estresse Oxidativo , Prognóstico , Estudos Prospectivos , Choque Cardiogênico/etiologiaRESUMO
BACKGROUND: The identification of high-risk heart failure (HF) patients makes it possible to intensify their treatment. Our aim was to determine the prognostic value of a newly developed, high-sensitivity troponin I assay (Atellica®, Siemens Healthcare Diagnostics) for patients with HF with reduced ejection fraction (HFrEF; LVEF < 40%) and HF with mid-range EF (HFmrEF) (LVEF 40%-49%). METHODS AND RESULTS: A total of 520 patients with HFrEF and HFmrEF were enrolled in this study. Two-year all-cause mortality, heart transplantation, and/or left ventricular assist device implantation were defined as the primary endpoints (EP). A logistic regression analysis was used for the identification of predictors and development of multivariable models. The EP occurred in 14% of the patients, and these patients had higher NT-proBNP (1,950 vs. 518 ng/l; p < 0.001) and hs-cTnI (34 vs. 17 ng/l, p < 0.001) levels. C-statistics demonstrated that the optimal cut-off value for the hs-cTnI level was 17 ng/l (AUC 0.658, p < 0.001). Described by the AUC, the discriminatory power of the multivariable model (NYHA > II, NT-proBNP, hs-cTnI and urea) was 0.823 (p < 0.001). Including heart failure hospitalization as the component of the combined secondary endpoint leads to a diminished predictive power of increased hs-cTnI. CONCLUSION: hs-cTnI levels ≥ 17 ng/l represent an independent increased risk of an adverse prognosis for patients with HFrEF and HFmrEF. Determining a patient's hs-cTnI level adds prognostic value to NT-proBNP and clinical parameters.
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Insuficiência Cardíaca , Modelos Cardiovasculares , Volume Sistólico , Troponina I/sangue , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Coração Auxiliar , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Taxa de SobrevidaRESUMO
BACKGROUND/AIMS: The pathophysiology of acute kidney injury (AKI) in ST-elevation myocardial infarction (STEMI) patients remains poorly explored. The involvement of the nitric oxide (NO) pathway has been demonstrated in experimental ischemic AKI. The aim of this study was to assess the predictive value of circulating biomarkers of the NO pathway for AKI in STEMI patients. METHODS: Four hundred and twenty-seven STEMI patients treated with primary percutaneous coronary intervention were included. The primary end point was AKI. Biomarkers of the NO pathway (plasma superoxide dismutase [SOD], uric acid, nitrite/nitrate [NOx], neopterin) as well as cardiac biomarkers (B-type natriuretic peptide [BNP] and troponin) were sampled 12 h after admission. The predictive value of circulating biomarkers was evaluated in addition to the multivariate clinical model. RESULTS: AKI developed in 8.9% of patients. The 3-month mortality was significantly higher in patients with AKI (34.2 vs. 4.1%; p < 0.001). SOD, uric acid, NOx, neopterin, BNP and troponin were significantly associated with the development of AKI (area under curve [AUC]-receiver operating curve [ROC] ranging between 0.70 and 0.81). In multivariate analysis cardiogenic shock, neopterin, NOx and troponin were independent predictors of AKI. AUC-ROC of the association of multibiomarkers and clinical model was 0.90 and outperformed the predictive value of the clinical model alone. OR of NOx ≥45 µmol/L was 8.0 (95% CI 3.1-20.6) for AKI. CONCLUSION: Biomarkers of the NO pathway are associated with the development of AKI in STEMI patients. These results provide insights into the pathophysiology of AKI and may serve at developing preventing strategies for AKI targeting this pathway.
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Injúria Renal Aguda/etiologia , Infarto do Miocárdio/complicações , Óxido Nítrico/metabolismo , Intervenção Coronária Percutânea/efeitos adversos , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Síndrome Cardiorrenal/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Peptídeo Natriurético Encefálico/metabolismo , Estresse Oxidativo/fisiologia , Intervenção Coronária Percutânea/métodos , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Choque Cardiogênico/complicações , Choque Cardiogênico/metabolismo , Troponina/metabolismoRESUMO
Accurate evaluation of the appearance of QTc sex differences during childhood and adolescence is intricate. Inter-subject differences of individual QT/RR patterns make generic heart rate corrections inaccurate because of fast resting heart rates in children. The study investigated 527 healthy children and adolescents aged 4-19 years (268 females, 50.9%). All underwent continuous ECG 12-lead monitoring while performing postural changes during a 70-min investigative protocol to obtain QT interval measurements at different heart rates. On average, more than 1200 ECG measurements (QT interval and its 5-min history of preceding RR intervals) were made in each subject. Curvilinear QT/RR regression involving intra-individual correction for QT/RR hysteresis were calculated in each subject. The projection of the QT/RR regressions to the heart rate of 60 beats per minute defined individually corrected QTc intervals. In males, gradual QTc shortening by about 15 ms appeared during the ages of 13-19 years synchronously with the incidence of secondary sex signs (p = 0.016). On the contrary, whilst gradual QTc prolongation by about 10 ms appeared in females, it occurred only during ages 16-19 years and was not related to the incidence of secondary sex signs (p = 0.18). The study also showed that in children and adolescents, linear QT/RR models fit the intra-subject data significantly more closely than the log-linear models (p < 0.001). The study speculates that hormonal shifts during puberty might be directly responsible for the QTc shortening in males but that QTc prolongation in females is likely more complex since it was noted to follow the appearance of secondary sex signs only after a considerable delay.
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INTRODUCTION: Patients with cardiogenic shock (CS) are at a high risk of developing infectious complications; however, their early detection is difficult, mainly due to a frequently occurring noninfectious inflammatory response, which accompanies an extensive myocardial infarction (MI) or a postcardiac arrest syndrome. The goal of our prospective study was to describe infectious complications in CS and the immune/inflammatory response based on a serial measurement of several blood-based inflammatory biomarkers. METHODS: Eighty patients with CS were evaluated and their infections were monitored. Inflammatory markers (C-reactive protein, procalcitonin, pentraxin 3, presepsin) were measured seven times per week. The control groups consisted of 11 patients with ST segment elevation myocardial infarction without CS and without infection, and 22 patients in septic shock. RESULTS: Infection was diagnosed in 46.3% of patients with CS; 16 patients developed an infection within 48âh. Respiratory infection was most common, occurring in 33 out of 37 patients. Infection was a significant or even the main reason of death only in 3.8% of all patients with CS, and we did not find statistically significant difference in 3-month mortality between group of patients with CS with and without infection. There was no statistically significant prolongation of the duration of mechanical ventilation associated with infection. Strong inflammatory response is often in patients with CS due to MI, but we found no significant difference in the course of the inflammatory response expressed by evaluated biomarkers in patients with CS with and without infection. We found a strong relationship between the elevated inflammatory markers (sampled at 12âh) and the 3-month mortality: the area under the curve of receiver operating characteristic ranged between 0.683 and 0.875. CONCLUSION: The prevalence of infection in patients with CS was 46.3%, and respiratory tract infections were the most common type. Infections did not prolong statistically significantly the duration of mechanical ventilation and did not increase the prevalence of hospital mortality in this high-risk CS population. CS due to acute myocardial infarction was accompanied by a strong and highly variable inflammatory response, but it did not reach the intensity of the inflammatory response observed in patients with septic shock. An extensive immune/inflammatory response in patients with CS is linked to a poor prognosis.
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Biomarcadores/metabolismo , Choque Cardiogênico/imunologia , Choque Cardiogênico/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Calcitonina/metabolismo , Feminino , Mortalidade Hospitalar , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/metabolismo , Fragmentos de Peptídeos/metabolismo , Prognóstico , Estudos Prospectivos , Curva ROC , Fatores de Risco , Componente Amiloide P Sérico/genética , Componente Amiloide P Sérico/metabolismo , Choque Cardiogênico/sangue , Choque Séptico/sangue , Choque Séptico/imunologia , Choque Séptico/metabolismoRESUMO
Limited evidence suggests that specificity of cardiac troponin T (cTnT), a highly sensitive biomarker of myocardial injury, is reduced in patients with skeletal myopathies. Whether amyotrophic lateral sclerosis (ALS)-the most common motor neuron disease-could be also associated with abnormal plasma or serum cTnT levels remains unclear. Our objective was to assess cTnT levels in patients with ALS without known cTnT elevating conditions. Among ALS patients seen at our institution until 2012 we identified those who had their cTnT measured. Patients who suffered from conditions known to elevate cTnT were excluded. A case-control analysis comparing cTnT levels of these ALS patients to matched non-ALS controls fulfilling the same inclusion criteria was performed. We included 40 ALS patients of whom 27 (68 %) patients had a positive cTnT. In the control group (n = 40), 2 (5 %) tested as cTnT positive (p < 0.001). Among the ALS patients who underwent cTnT evaluation on more occasions (n = 7; median follow-up = 1.08 years), 2 (29 %) patients tested positive during the initial measurement while 6 (86 %) of them had positive cTnT at the subsequent evaluations. ALS patients with increased cTnT had been diagnosed with ALS significantly earlier than those without the elevation. Our findings raise the possibility that ALS may cause cTnT elevations. Further studies are needed to confirm these findings, clarify the pathophysiological mechanism, and establish the significance of cTnT elevations in patients with ALS.
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Esclerose Lateral Amiotrófica/sangue , Biomarcadores/sangue , Troponina T/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/mortalidade , Estudos de Casos e Controles , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
BACKGROUND: The Zwolle score is recommended to identify low-risk patients eligible for early hospital discharge after ST-elevation myocardial infarction (STEMI), but since only one third of STEMI has low Zwolle score, hospital discharge is frequently delayed. B-type natriuretic peptide (BNP) also provides prognostic information after STEMI. The aim of the study was to test the hypothesis that patients with high Zwolle score associated with low BNP share similar outcomes than those with low Zwolle score. METHODS AND RESULTS: The study population consisted of 1032 consecutive STEMI patients in whom BNP was measured 24h after chest pain onset. The area under the curve of Zwolle score and plasma BNP for 30-day mortality were 0.82 and 0.87, p=0.39. A BNP threshold of 200pg/ml had sensitivity of 100% and specificity of 34% for predicting 30-day mortality. Patients with high Zwolle score and BNP≤200pg/ml (n=183) had similar mortality and hospital stay to those with low Zwolle score (0% vs. 0.5% and 5 vs. 5days, both p=1.0). By contrast, patients with high Zwolle score and BNP>200pg/ml had the highest mortality (6.7%) and the longest hospital stay (6days), both p<0.01. CONCLUSION: STEMI patients with high Zwolle score but low BNP share similar outcomes with those with low Zwolle score and should be eligible for early discharge. Hence, using the rule of "low-Zwolle or low-BNP" might increase the number of STEMI patients that might be eligible for early discharge.
Assuntos
Peptídeo Natriurético Encefálico/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Idoso , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Sensibilidade e Especificidade , Índice de Gravidade de DoençaRESUMO
Chemokines, including RANTES, play a crucial role in the processes of inflammation during cardiovascular disorders, including myocardial infarction, disease progression and complications. This study aimed to evaluate the role of RANTES -403G/A polymorphism and levels in circulation in processes of development and progression of myocardial infarction and cardiogenic shock. A total of 609 patients with ST-segment elevation myocardial infarction, 43 patients with cardiogenic shock and 130 control subjects were enrolled in the study. RANTES -403G/A promoter polymorphism and baseline serum RANTES levels were analyzed. In the present study, we associated RANTES -403G/A promoter polymorphism with acute heart failure in patients with myocardial infarction (p = 0.006) and ejection fraction 3 months after MI onset (p = 0.02). Further, a difference in circulating RANTES levels among controls and STEMI subjects, and a relation of serum levels with acute heart failure was observed (p = 0.03, p = 0.003, respectively). We found a significant difference when comparing cardiogenic shock patients and controls (p < 0.001), with the most significant difference between cardiogenic shock and AHF subgroup of STEMI patients (p < 0.001). We observed a decreasing tendency of serum RANTES levels with the severity of myocardial infarction and progression, with the lowest levels in patients with cardiogenic shock (cutoff level ≥80.4 ng/ml). Our results suggest the role of RANTES as a potential biomarker of cardiogenic shock and acute heart failure in the hospital phase after myocardial infarction.
Assuntos
Quimiocina CCL5/sangue , Quimiocina CCL5/genética , Insuficiência Cardíaca/genética , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Choque Cardiogênico/genética , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Progressão da Doença , Feminino , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Choque Cardiogênico/sangue , Choque Cardiogênico/patologia , Análise de SobrevidaRESUMO
OBJECTIVES: Neutrophil gelatinase-associated lipocalin (NGAL) from a pathophysiological perspective connects various pathways that affect the prognosis after myocardial infarction. The objective was to evaluate the benefits of measuring NGAL for prognostic stratification in addition to the Thrombolysis in Myocardial Infarction (TIMI) score, and to compare it with the prognostic value of B-type natriuretic peptide (BNP). DESIGN: Prospective observational cohort study. SETTING: One university/tertiary centre. PARTICIPANTS: A total of 673 patients with ST segment elevation myocardial infarction were treated by primary percutaneous coronary intervention. NGAL and BNP were assessed on hospital admission. PRIMARY OUTCOME: 1-year mortality. SECONDARY OUTCOMES: 1-year hospitalisation due to acute heart failure, unplanned revascularisation, reinfarction, stroke and combined end point of 1-year mortality and hospitalisation due to heart failure. STATISTICAL METHODS: Using the c-statistic, the ability of NGAL, BNP and TIMI score to predict 1-year mortality alone and in combination with readmission for heart failure was evaluated. The addition of the predictive value of biomarkers to the score was assessed by category free net reclassification improvement (cfNRI) and the integrated discrimination index (IDI). RESULTS: The NGAL level was significantly higher in non-survivors (67 vs 115â pg/mL; p<0.001). The area under the curve (AUC) values for mortality prediction for NGAL, BNP and TIMI score were 75.5, 78.7 and 74.4, respectively (all p<0.001) with optimal cut-off values of 84â pg/mL for NGAL and 150â pg/mL for BNP. The addition of NGAL and BNP to the TIMI score significantly improved risk stratification according to cfNRI and IDI. A BNP and the combination of the TIMI score with NGAL predicted the occurrence of the combined end point with an AUC of 80.6 or 82.2, respectively. NGAL alone is a simple tool to identify very high-risk patients. NGAL >110â pg/mL was associated with a 1-year mortality of 20%. CONCLUSIONS: The measurement of NGAL together with the TIMI score results in a strong prognostic model for the 1-year mortality rate in patients with STEMI.